Uniform tensioning device



June 2, 1953 A. JOHNSON 2,640,655

UNIFORM TENSIONING DEVICE Filed April 28, 1949 2 Shets-Sheet 1 IN VEN TOR. 4Lafir [fa/mm BY June 2, 1953 A. JOHNSON 2,640,655

UNIFORM TENSIONING DEVICE Filed April 28, 1949 2 Sheets-Sheet 2 7f// ij/m; 5 fw a o 4 7/ 75 54 f z 'u. j

, INVENTOR.

ALEEKT (fa/mm BY Maw Patented June 2, 1953 psi-rec stares rarest!" OFFICE 2,640,655 UNIFOR aENsIoni-NG DEvIor; b rt. Mess e erh N- Y- m r t pr 28, s ri l ewe Cere were.

This invention relates to a device for automatically maintaining a uniform tension on a strand of wire, thread and the like as the same is unwound from a spool or reel.

As the spools or reels vary in weight as well as in the quantity of material wound thereon, uneven tension in the take ofi of the material results unless provision is made for automatically producing a braking action on the spool or reel in relation to the weight of the spool'or reel and the material thereon. The invention therefore comprehends an improved device whereby sub.- stantially the same tension or pull on the strand is required to effect rotation of the spool or reel irrespective of the weight thereof or of the quantity of material wound thereon.

Another object of the invention is to provide a tensioning device mounted on a resiliently supported base which is movable for subjecting the spool. or reel to a, braking action in relation to the weight of the spool or reel and the material wound thereon.

Another object of the invention is the provision of means for automatically decreasing the braking action on the spool or reel shaft as the base swings upwardly with the take off of the material on the spool or reel.

Still another object of the invention is to pro-. vide a tensioning device of the indicated char-. acter in which means is provided for varying the resiliency of the base for accommodating differ: ent sizes of spools or reels.

With the foregoing and other objects .in View, reference is now made to the following specifi-cae tion and accompanying drawingsin which the preferred embodiment of the invention is illustrated.

In the drawings:

. F s a rspe t V ew o a uni o m te iqh e iee c nstr c e in rd hhe w th the invention.

2 s an l d agmenta y .YiQW ll ing the brake arms moved inwardly so as to teniQ l the brake hee e-ins h h s e ite when the platform is swung downwardly by the weight of the spool or reel.

3 is a m n ary ehd -i w showin th u o 9 W Shaft qr shu ing lh i. 9 .91 or reel.

Referring to the dra i s by ch iee e rs o reference the i hl de ic ihe e ee s has? (0 of stepped formation consistingofa bottom W l H hd h pp r all stepwise. t e e h ree e h O f t Patte n Well hr one vesse 's .enehdi shiehhe s I Pist ns in e erpla e lying relation withthe forward end of the loot!- tom wall H is a platform which is connected with the. upper wall I! by hinges l5 and which forms a support for the. tensioning means indi: cated generally by the reference character It.

The platform' i4 is resiliently supported for swinging movement from a substantially hori: zontal position to an inclined relation by a coil prin it connected at its upper endto anarm l8 projecting forwardly from the. upper Wall l2 oi the base and connected at its lowerend t an adjusting screw I9 carried by the platform 14. The arm t is hinged at its lower end it to the upper wall 12 and projects forwardly v therefrom in inclined relation. The said arm is a a e o be adj s ed fo ar in t e hr l har tion thereof in order to vary the tension on the h ne is b a s ew 21 s u ed to t e uppe all I 2 or w v l turn mov m and wh ch s rew threadedly engages through the arm It and is pr ide wi h a a Whee 2 at i s up er end for manually turning the same. The tension on the spri H is a s ada ted to b ried by m vem o a rider th eded e r-eased. oh h scre it and to whioh he low r n of he coil spring is attached. rider 723 is provided ith a depending an e ro e on 2 which is u e lv moun ed in a some sl t 2 m plat 2% eed d to he p r aceth la ih with th dense there f extend n unde th Th shrew !9 is sw ellv m unted. th hn llhte nd 21 and 28 of th late 26W; e f war end. o he s e r r d hglh h h the mm 21 a d provi ed w t I ah ulet he h ndle 29s T e mentionin 6 ihe ud a haft i2 o wh hh' a pool. r reel in ica tr -ther for sh s share-t e i mo nte fo rnin more meat r h sih i .Qii W e threa or he ik Wound ther on. he sha t 3.? e t nds tmhs erse v'qf th p a o m 14. nd s iq r a ed n bearin s 3 mounted on blocks ent ced to the platform ads ieqehtihe liar-Ward ed the Arran ed on his ee uter and 0 the sha a brak drum hav n a cylin rica per her ad pted t en a ed b oppos t ly. di posed arc a h sh es it nd fo n h nq e a brakin action n th ha h bra s oes 36 and 31 are arranged within oppositelydisposed arcuate por tions 38 and 39 of brake arms 49 and 4| affixed at their lower ends to an angle bracket 42 SE? a. an eqerte b e meted th arts. nd

cured to the platform .44 with theupwardly pro: e tihe o osi el dispo ed par ll l ends 5 and 4 o aid. Mal -earms d s o ed i spac d e e iqh y from each other for varying the tension of the brake shoes against the periphery of the brake drum.

In order to move the brake arms 40 and 41 toward and away from each other for varying the braking action on the shaft 32, rock arms 45 and 46 are provided which are secured together intermediate their ends for pivotal rocking movement by a screw 41 extending therethrough medially of the length thereof. Below said pivotal connection the rock arms extend outwardly and have downwardly extending terminals 48 and 49 at their lower ends through which protrudes a screw 56 slidably mounted in aligned openings i in the ends 43 and 44 of the brake arms. Coil springs 52 and 53 are arranged on said screw between the terminals 68 and 49 and the ends 43 and d4 of the brake arms respectively. Wing nuts l! and i8 threadedly engaging the ends of the screw 59 retain the downwardly extending terminals 48 and lid on the screw and may betightened thereagainst to vary the tension of the coil springs 52 and 53. A coil spring 54 is also arranged on said screw between the ends 43 and M' of the brake arms for normally maintaining the said arms in resiliently spaced relation. The rock arms also include upwardly projecting ends 55 and 56 which are disposed on opposite sides of a cam 5'1 mounted on a rock shaft 58 rigidly afiixed at its inner end to an arm 59. The arm 59 is pivotally attached to a bar Gil pivoted as at El to the upper end of a standard 62 mounted in upright relation on the base l0 adjacent the forward edge of the upper wall I2.

The rock shaft'58 is mounted for rocking .movement in a horizontal bearing 63 arranged on the upper end of a standard 65 amxed at its lower end to one of the blocks B l. Arranged on the rock shaft 58 are spaced circular heads 65 and 66 located at oppositeends of the cam 51 and between which heads the upper ends 55 and 56 of the rock arms and id are disposed in engagement with the cam 5?. The heads 65 and 66 constitute guides for retaining the upper ends and 5B of the rock arms in alignment on opposite sides of the cam.

- The shaft 32 is flanged as at ill between the spaced bearings 33 which permits of the replacement of the outer end 68 of said shaft and the substitution of a shaft end 59 as shown in Fig. 3

of the drawings. The shaft end 69 is supported at its outer end in a bearing lil mounted on a replaceable block for accommodating a large or heavy spool or reel indicated by the reference character B, which with the material wound thereon may weigh several hundred pounds. The spools or reels A and B are secured on the shaft ends 68 and 69 respectively by conical shaped wedges l2 and 13 slidably fitted on said shaft ends and which are tightened in the bore or axle of the spool or reel by nuts M which also secure the spool or reel to the shaft.

The platform l4 may also be resiliently supported by springs 15 arranged between the platform and the base adjacent the forward end thereof. Said springs are particularly important when heavy spools are employed as shown in Fig. 3 of the drawings while the tension on the platform M by the coil spring H is adapted to bevaried so as to vary the braking action of the brake shoes against the brake drum. The platform 14 is thereby balanced and moves downwardly with the weight of the spool thereon so as to move the rock arms to thereby move the brake'arms to exert pressure of the brake shoes 4 against said drum in relation to the wei ht of the spool imposed on the platform. As the strand is unwound from the spool, the platform will rise and the braking action on the shaft will decrease.

What is claimed is:

1. In a device for tensioning the unwinding of a strand from a spool, a base, a platform balanced on said base and having upward movement, a shaft rotatably supported on said platform and adapted to receive a spool for turning the shaft by the unwinding of the strand therefrom, brake shoes, oppositely disposed brake arms carried by said platform and having resiliently spaced ends and mounting said shoes for braking action on the shaft, oppositely disposed rock arms carried by said spaced ends of the brake arms, resilient means arranged between said spaced ends of the brake arms for exerting an outward tension on the brake arms and resilient means arranged between said spaced ends and the rock arms for exerting inward tension on the brake arms by inward movement of the rock arms/a, second rotatable sh'ait supported by said platform and having a cam arranged between said rock arms for moving the rock arms to vary the tension of said resilient means on said brake arms, and a lever affixed to said second mentioned shaft and pivotally supported at its opposite end by said base for rotating said shaft with the movement of the platform to thereby exert braking action of the shoes on the shaft in relation to the weight of the spool supported on the platform.

2. In a device for tensioning the unwinding of a strand from a spool, a base, a platform balanced on said base and having upward movement, a shaft rotatably supported on said platform and adapted to receive a spool for turning the shaft by the unwinding of the strand therefrom, brake shoes, oppositely disposed brake arms carried by said platform and having spaced ends and mounting said shoes for braking action on the shaft, oppositely disposed rock arms connected together for pivotal rocking movement and adjustably carried by the spaced ends of the brake arms, resilient means arranged between said spaced ends of the brake arms for exerting an outward tension on the brake arms and resilient means arranged between said spaced ends and the rock arms for exerting inward tension on the brake arms by inward movement of the rock arms, a second rotatable shaft supported by said platform and having a cam arranged between said rock arms for moving the rock arms to vary the tension of said resilient means on said brake arms, a lever affixed to said second mentioned shaft and pivotally supported at its opposite end by said base for rotating said shaft with the movement of the platform to thereby exert braking action of the shoes on the shaft in relation to the weight of the spool supported on the platform, and means engaging said rock arms for adjusting the tension of said resilient means against the brake arms.

3. In a device for tensioning the unwinding of a strand from a spool, a base, a platform balanced on said base and having upward movement, a shaft rotatably supported on said platform and adapted to receive a spool for turning the shaft by the unwinding of the strand therefrom, brake shoes, oppositely disposed brake arms carried by said platform and having spaced ends and mounting said shoes for braking action on the shaft, a bar slidably disposed in openings in said spaced ends, oppositely disposed rock arms connected together for pivotal rocking movement and slidably arranged on said bar, resilient means arranged between said spaced ends of the brake arms for exerting an outward tension on the brake arms and resilient means arranged'between said spaced ends and the rock arms for exerting inward tension on the brake arms by inward movement of the rock arms, a second rotatable shaft supported by said platform and having a cam arranged between said rook arms for moving -the rock arms to vary the tension of said resilient" means on said brake arms, a lever afiixed to said second mentioned shaft and pivotally supported at its opposite end by said base for rotating said shaft with the movement of the platform to thereby exert braking action of the shoes on the shaft in relation to the weight of the spool supported on the platform, and means adjustably securing said rock arms on said bar for varying the tension of said resilient means against said spaced ends.

ALBERT JOHNSON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 648,273 Lindstrom Apr. 24, 1900 793,929 Harrington July 4, 1905 857,272 Enrico June 18, 1907 925,304 Cummings June 15, 1909 993,550 Robeson May 30, 1911 Hufi June 19, 1923 

